JRE 8 rt.jar is the JAR file for JRE 8 RT (Runtime) libraries. JRE (Java Runtime) 8 is the runtime environment included in JDK 8. JRE 8 rt.jar libraries are divided into 6 packages:

com.* - Internal Oracle and Sun Microsystems libraries
java.* - Standard Java API libraries.
javax.* - Extended Java API libraries.
jdk.* -  JDK supporting libraries.
org.* - Third party libraries.
sun.* - Old libraries developed by Sun Microsystems.

JAR File Information:

Directory of C:\fyicenter\jdk-1.8.0_191\jre\lib
      63,596,151 rt.jar

Here is the list of Java classes of the com.* package in JRE 1.8.0_191 rt.jar. Java source codes are also provided.

⏎ com/sun/jmx/snmp/SnmpUnsignedInt.java

/*
 * Copyright (c) 1997, 2007, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 *
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 */


package com.sun.jmx.snmp;



/**
 * Is the base for all SNMP syntaxes based on unsigned integers.
 *
 * <p><b>This API is a Sun Microsystems internal API  and is subject
 * to change without notice.</b></p>
 */

public abstract class SnmpUnsignedInt extends SnmpInt {

    /**
     * The largest value of the type <code>unsigned int</code> (2^32 - 1).
     */
    public static final long   MAX_VALUE = 0x0ffffffffL;

    // CONSTRUCTORS
    //-------------
    /**
     * Constructs a new <CODE>SnmpUnsignedInt</CODE> from the specified integer value.
     * @param v The initialization value.
     * @exception IllegalArgumentException The specified value is negative
     * or larger than {@link #MAX_VALUE SnmpUnsignedInt.MAX_VALUE}.
     */
    public SnmpUnsignedInt(int v) throws IllegalArgumentException {
        super(v);
    }

    /**
     * Constructs a new <CODE>SnmpUnsignedInt</CODE> from the specified <CODE>Integer</CODE> value.
     * @param v The initialization value.
     * @exception IllegalArgumentException The specified value is negative
     * or larger than {@link #MAX_VALUE SnmpUnsignedInt.MAX_VALUE}.
     */
    public SnmpUnsignedInt(Integer v) throws IllegalArgumentException {
        super(v);
    }

    /**
     * Constructs a new <CODE>SnmpUnsignedInt</CODE> from the specified long value.
     * @param v The initialization value.
     * @exception IllegalArgumentException The specified value is negative
     * or larger than {@link #MAX_VALUE SnmpUnsignedInt.MAX_VALUE}.
     */
    public SnmpUnsignedInt(long v) throws IllegalArgumentException {
        super(v);
    }

    /**
     * Constructs a new <CODE>SnmpUnsignedInt</CODE> from the specified <CODE>Long</CODE> value.
     * @param v The initialization value.
     * @exception IllegalArgumentException The specified value is negative
     * or larger than {@link #MAX_VALUE SnmpUnsignedInt.MAX_VALUE}.
     */
    public SnmpUnsignedInt(Long v) throws IllegalArgumentException {
        super(v);
    }

    // PUBLIC METHODS
    //---------------
    /**
     * Returns a textual description of the type object.
     * @return ASN.1 textual description.
     */
    public String getTypeName() {
        return name ;
    }

    /**
     * This method has been defined to allow the sub-classes
     * of SnmpInt to perform their own control at intialization time.
     */
    boolean isInitValueValid(int v) {
        if ((v < 0) || (v > SnmpUnsignedInt.MAX_VALUE)) {
            return false;
        }
        return true;
    }

    /**
     * This method has been defined to allow the sub-classes
     * of SnmpInt to perform their own control at intialization time.
     */
    boolean isInitValueValid(long v) {
        if ((v < 0) || (v > SnmpUnsignedInt.MAX_VALUE)) {
            return false;
        }
        return true;
    }

    // VARIABLES
    //----------
    /**
     * Name of the type.
     */
    final static String name = "Unsigned32" ;
}

⏎ com/sun/jmx/snmp/SnmpUnsignedInt.java

Or download all of them as a single archive file:

File name: jre-rt-com-1.8.0_191-src.zip
File size: 8099783 bytes
Release date: 2018-10-28
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